title: Determination of remifentanil in human plasma by liquid chromatography-tandem mass spectrometry utilizing micro extraction in packed syringe (MEPS) as sample preparation.
abstract: Remifentanil is a synthetic short-acting opioid with a short half-life that is being used during anaesthesia of small children. In this work an LC-MS/MS method for remifentanil quantification in 20 μL volume of human plasma was developed and validated in connection with a clinical study on neonatal children. Sample preparation was performed with micro extraction in packed syringe (MEPS), which is a miniaturization of solid phase extraction. For this method a mixed phase sorbent M1 (C8, cation exchange), and a protocol for basic compound extraction was followed. Remifentanil-(13)C(6) was used as internal standard. For chromatographic separation, a C18 analytical column with gradient elution was used with mobile phase consisting of aqueous 0.1% formic acid and methanol. The total analysis time was 5.0 min and the measuring range was between 0.05 and 50 ng/mL. Precision and accuracy were with acceptance criteria of ±15%. Plasma samples were stable for 5 weeks at -20°C and for 4h at room temperature while 50% was lost after 24h. This method was successfully applied for remifentanil determination in clinical samples and results agreed with a reference method. With this method using MEPS, a low limit of quantification and much reduced sample volume was obtained as compared with previous methods.
authors.affiliation: Department of Medicine, Division of Clinical Pharmacology, Karolinska University Hospital, Stockholm, Sweden. rana_f7@yahoo.com
authors.forename: Rana
authors.initials: R
authors.lastname: Said
authors.forename: Anton
authors.initials: A
authors.lastname: Pohanka
authors.forename: Maria
authors.initials: M
authors.lastname: Andersson
authors.forename: Olof
authors.initials: O
authors.lastname: Beck
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abdel-Rehim
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D016018:Least-Squares Analysis; D010880:Piperidines / Q000097:blood* / Q000737:chemistry; D000077208:Remifentanil; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D052617:Solid Phase Microextraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D010880:Piperidines; D000077208:Remifentanil